LSAT PT34, S2 Logical Reasoning, Q4, For newborns of age four to six weeks whose mothers …

Why is (C) the answer and not (B)?

Why would hearing the voice of a mother who is a primary caregiver stop a newborn of 4-6 weeks from crying temporarily? And why would hearing the voice of someone else not?

It's reasonable to say it's because these babies recognize the voices of their primary caregivers, that they are nearby, and there is no need to continue crying because, in a sense, aid is likely on its way.

Even if we tried going with (B), it's a little extreme, based on the passage, to say a mother's voice is the FIRST thing these babies learn to recognize. And even if they did, simply recognizing a voice doesn't explain why the crying stops necessarily. It's because it's the voice of the primary caregiver - not the voice of the mother per se.

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